With many conventional luminaires that incorporate edgelit lightguides, the light source needs to touch or be extremely close to an edge of the lightguide in order to achieve efficient transfer of light from the light source into the lightguide. When the light source includes light emitting diodes and the lightguide is formed of typical optical polymers, thermal properties of the optical polymer and the surface temperature of the light emitting diodes can limit the maximum drive current, and thus maximum light output, of the light emitting diodes. For example, the light emitting diodes may be constrained to operate at a relatively low light output so that the heat generated by the operation of the light emitting diodes does not adversely impact and damage the lightguide's polymeric material. The surface temperature of the light emitting diodes or the heat generated by operating the light emitting diodes can be reduced by using large heat sinks or similar bulky structures. However, with many compact systems, it can be impractical or undesirable to utilize such large heat sinks or other bulky structures for heat removal. Further, such large heat sinks or bulky structures may not be cost effective. An alternative to using the large heat sinks or similar structures is to space the light emitting diodes farther away from the edge of the lightguide. However, the spacing of the light emitting diodes from the edge of the lightguide may adversely affect the light transfer from the light emitting diode to the lightguide when undertaken with conventional technical approaches.
Accordingly, need exists for technology to space one or more light emitting diodes away from the lightguide while achieving appropriate light transfer into the lightguide. Need further exists to provide flexibility in the alignment between the light emitting diodes and the lightguide. Need further exits to manipulate the output of the lightguide based on manipulating the manner in which light is coupled into the lightguide.